CZ20004251A3 - UV-stable polyether ester copolymeric composition and its use in the form of a foil - Google Patents

Abstract

The invention relates to a polyetherester copolymer composition having a strongly improved UV stability, which is eminently suitable for use in film. The polyestherester copolymer composition according to the invention contains 0.1-10 wt.% activated carbon and 0.05-3 wt.% of a hindered amine light stabilizer (HALS). Preferably, the contents are 0.5-3 and 0.2-1 wt.%, respectively. At a film thickness of 100 mu m an increase in the life on the order of a factor 2, relative to the effect of the sum of the individual components, appears to be possible. Preferably, the molecular weight of the HALS is higher than 1500.

Description

The present invention relates to an elastomeric copolyetherester film with improved UV resistance to aging.

BACKGROUND OF THE INVENTION

Elastomeric copolyetherester film is increasingly being used as a surface layer in moisture-regulating roofing and is also used in construction. During construction, the film is often exposed to direct sunlight for most of the time before the roof tiles are laid. Especially in mountainous areas, UV light can be very intense. Irradiation with UV rays causes very rapid deterioration of the mechanical properties of the unprotected film, with the result that the film can be very slightly damaged, for example by falling tools. In more extreme cases, it is no longer possible to step on the roof covering without being damaged. In addition, the moisture control properties are also adversely affected. '

Encyclopaedia of Polymer Science and Engineering No. 12, p.102 (1988) by John Wiley and Sons, Inc, discloses that copolyetheresters can be effectively protected from UV radiation by the addition of 0.5 to 3 wt. percent active coal. The same Encyclopaedia vol. 15, pp. 563-564 (1989) further states that a good dispersion of activated carbon is necessary,

wherein the particle size should be between 15 and 25 nanometers. These findings, through which the copolyetherester film would have good UV stability and improved infrared shrinkage resistance, are repeated in the claims of European Patent Application No. 0783016-A2. However, with respect to said advantages or any particular effect, in this European patent application No. 0783016-A2 the authors of the present invention were unable to provide any experimental evidence for them. On the contrary, it turns out that the UV resistance of the carbon black-containing copolyetherester film, particularly with respect to the membranes mentioned in claim 14 of said patent, with a thickness of 5 to 30 microns, differs only slightly from the UV resistance of the unstabilized membranes.

The prior art UV stabilized copolyetherester films appear to be completely incapable of withstanding the harsh conditions to which the films are exposed, particularly in the construction industry.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a copolyetherester composition which, although used in the form of a very thin film, has a substantially improved UV resistance in order to be able to use it, inter alia, as a moisture-regulating roofing layer.

This object was achieved with a copolyetherester composition comprising a stabilizer composed of 0.1 to 10 weight percent activated carbon and 0.1 to 3 weight percent hindered amine light stabilizer (HALS). Use of HALS in copolyetherester composition • 0

·· - 0 0 · 0 • 0 • 0 0 • · 5 <· • · - 0 0> * 0 • 0 0 0 0 0 0 0 · 0 0 • '0 · • 0 · 0 0 · 0 0 · 0 • 0

it has been known for a long time to improve stability, and is described, inter alia, in Japanese Patent No. 52,04869-A. Combinations of HALS with other UV stabilizers are known to be useful for improving HALS activity. In Japanese patent no.

No. 015455-A, United States Patent

No. 4,524,165-A and Japanese Patent Publication No. 02 283754 disclose a combination with triazole and Japanese Patent Publication No. 6,024,165.

337.349-A combination with thioether. The inventors have so far tested these and some other combinations of UV stabilizers, but none of them has provided sufficient stability for use in the film.

It is very surprising that the combination with activated carbon on the other hand provides such a marked improvement in UV resistance that even a very thin polyetherester film can be exposed to direct UV radiation for a long time.

The copolyether esters included in this composition include copolyether esters derived from polyether glycols having an average molecular weight of 600 to 6000, glycols, preferably alkylene glycols, for example ethylene glycol or butylene glycol, and dicarboxylic acids, for example aromatic dicarboxylic acids, preferably terephthalic acid and terephthalic acid. naphthalenedicarboxylic acids, cycloaliphatic dicarboxylic acids, for example from cyclohexanedicarboxylic acid, and aliphatic dicarboxylic acids, for example from adipic acid.

Examples and preparation of such copolyetheresters are described, inter alia, in Thermoplastic Elastomers,

2nd Edition, Chapter 8, Carl Hanser Verlag (1996) ISBN 1-56990-205-4, Handbook of Thermoplastic, ed. O. Otabisi, Chapter 17, Marcel Dekker Inc, New York 1997, ISBN •

0-8247-9797-3, Encyclopaedia of Polymer Science and Engineering, Vol. 12, pp.75-117 and references cited therein. A large number of copolyetheresters are available commercially.

The ratio between the polyester units derived from polyether glycol and the units derived from alkylene glycol, i.e. the ratio between the soft and hard segments of the copolyether ester, may vary within a wide range and depends mainly on its use for the polyether ester copolymer. Generally, this ratio will be chosen so that the Shore hardness of the polymer is between 25 and 80.

The moisture-regulating capacity of membranes made of a polyetherester copolymer is varied as desired by varying the thickness of the membrane or varying the carbon: oxygen ratio of the polyalkylene oxide glycols in the polyetherester copolymer. Usually the value of this ratio is between 2 and 4.3, with a low ratio mostly leading to an increase in water vapor permeability.

Activated carbon in this context means a specific form of carbon consisting of very fine primary particles combined into primary aggregates that are not comminuted under normal dispersion conditions. These primary aggregates are usually gradually combined into agglomerates. This activated carbon is characterized by a large optically available surface area. This surface area is determined primarily by the size of the primary particles and the degree of their packaging into the primary aggregates. Activated carbon can be obtained in various embodiments in properties and is commercially available in various forms and under different trade names. In a preferred embodiment, carbon black is used. It is preferred that they be under the conditions of preparation of the composition

·· • ·· ·· ·· • v • * · · · · - 5 r · • · • · · · • · • · · • · · · · · · · • · · ·

all agglomerates are comminuted into primary aggregates which should form a good dispersion in the composition. . The diameter of the primary particles may vary over a wide range, for example between 10 and 100 nanometers. In a preferred embodiment, the average particle size is selected to be between about 15 and 40 nanometers. When the particles are smaller, the absorption capacity of the radiation decreases significantly, as radiation may bend around the particle. When the particles are larger, the optically available surface area decreases very significantly, and the diameter of the primary aggregates may sometimes be too large, causing problems in processing into thin films.

The activated carbon content of the composition may, in principle, vary within a wide range, for example between 0.1 and 10% by weight. Since lower concentrations exhibit relatively little effect, and at concentrations above 3% by weight, UV radiation is absorbed only to a slightly greater extent, preferably the content is limited to between 0.5 and 5% by weight and even more preferably to 0.5% by weight. up to 3 weight percent. A suitable upper limit is usually such that the surface layer of the composition is no longer transparent. Therefore, a higher carbon content is suitable for a very thin film than for a stronger film. Last but not least, it should also be noted that higher carbon contents usually have an adverse effect on mechanical properties, such as elongation (elongation at break).

The sterically hindered amine light stabilizer (HALS) of the composition of the invention is a UV light stabilizer for copolyetherester compositions that is often used by those skilled in the art. The HALS described in European Patent No. 000389-B1, bis- (1,2,2,6,6-pentamethylpiperidyl) - (3 ´, 5´-di-tert-butyl-

 φ ·· · φ φ φ φ φ

6 _ I · φ · φ φ • • • • • • • • •

-4'-hydroxybenzyl) butyl malonate, available under the tradename 'Timivin 144 from Ciba-Geigy.

The term steric hindered amine light stabilizer is understood to mean substances having the following general formulas

^R i - ^R p

Jk-

In these formulas to represent independently of one another different substituents. Suitable substituents include, for example, hydrogen, ether groups, ester groups, amino groups, amide groups, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, cycloalkyl groups and aryl groups, wherein the individual substituents may contain functional groups; examples of functional groups include alcohol groups, ketone groups, anhydride groups, imine groups, siloxane groups, ether groups, carboxyl groups, aldehyde groups, ester groups, amide groups, imide groups, amino groups, nitrile groups, ether groups, urethane groups groups and any various combinations of said groups. The amine light stabilizer may also form part of the polymer. -. ·

In a preferred embodiment, the HALS component selected is a compound that is derived from a substituted piperidine compound, in particular any compound derived from a ^1-7 alkyl-substituted piperidyl compound, a piperidinyl compound or a piperazinone compound, and substituted alkoxypiperidinyl compounds. Examples of such substances are:

* 2,2,6,6-tetramethyl-4-piperidone;

* 2,2,6,6-tetramethyl-4-piperidinol;

* bis- (1,2,2,6,6-pentamethylpiperidyl) - (3 ', 5'-di-tert-butyl-4'-hydroxybenzyl) butyl malonate;

* di- (2,2,6,6-tetramethyl-4-piperidyl) sebacate (Tinuvin 770); The oligomer of N- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol and succinic acid (Tinuvin 622);

* cyanuric acid and N, N-di (2,2,6,6-tetramethyl-4-piperidyl) -hexamethylenediamine oligomer;

Bis (2,2,6,6-tetramethyl-4-piperidinyl) succinate;

* bis- (1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 123);

* bis- (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate (Tinuvin 765);

tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butane tetracarboxylate;

* N, N'-bis- (2,2,6,6-tetramethyl-4-piperidyl) -hexane-1,6-diamine (Chimasorb T5);

* N-butyl-2,2,6,6-tetramethyl-4-piperidinamine;

* 2,2 '- [(2,2,6,6-tetramethyl-piperidinyl) -imino] bis- [ethanol];

* (6-morpholine-5-triazine-2,4-diyl) (2,2,6,6-tetramethyl-4-piperidinyl) -iminohexamethylene- (2,2,6,6-tetramethyl-4-piperidinyl) (imino) (Cyasorb UV 3346);

* 5- (2,2,6,6-tetramethyl-4-piperidinyl) -2-cycloundecyloxazole) (Hostavin N20);

* 1,1 '- (1,2-ethane-diyl) -bis (3,3', 5,5'-tetramethyl-piperazinone);

* 8-acetyl-3-dothecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro (4,5) deca-2,4-dione;

* polymethylpropyl-3-oxy- [4 (2,2,6,6-tetramethyl) piperidinyl] siloxane (Uvasil 299);

* 1,2,3,4-butane-tetracarboxylic acid 1,2,3-tris (1,2,6,6-pentamethyl-4-piperidinyl) -4-tridecyl ester;

* α-methylstyrene-N- (2,2,6,6-tetramethyl-4-piperidinyl) maleimide-N-stearylmaleimide copolymer;

* 1,2,3,4-butanetetracarboxylic acid 1,2,2,4,6-pentamethyl-4-piperidinyl ester polymer with beta, beta, beta, beta'-tetramethyl-2,4,8,10-tetraoxaspiro [ 5.5] undecane-3,9-diethanol (Mark LA63);

* 2,4,8,10-tetraoxaspiro [5.5] undecane-3,9-diethanol, beta, beta, 2,2,6,6-tetramethyl-4-piperidinyl ester polymer

beta ', beta-tetramethyl (Mark LA68);

* 1,3: 2,4-bis-O- (2,2,6,6-tetramethyl-4-piperidinylidene) D-glucitol (HALS 7);

* 7-oxa-3,20-diazadispiro [5.1.11.2] -heneicosan-21-one, 2,2,4,4-tetramethyl-20- (oxiranylmethyl) u oligomer (Hostavin N30);

Propanedioic acid [(4-methoxyphenyl) methylene] -bis- (1,2,2,6,6-pentamethyl-4-piperidinyl) ester (Sanduvor PR 31);

* Ν, Ν´-1,6-hexanediyl-bis [N- (2,2,6,6-tetramethyl-4-piperidinyl)] formamide (Uvinul 4050H).

* N, N '' - [1,2 'ethanediylbis [[[4,6-bis [butyl (1,2,2,6,6pentamethyl-4-piperidinyl) amino] -1,3,5-triazine]] -2-yl] -imino] -3,1-propanediyl]] - bis [N ', N' '- dibutyl-N', N '' - bis (1,2,2,6,6-pentamethyl-4) -piperidinyl) -1,3,5-triazine-2,4,6-triamine (Chimassorb 119);

* an acid bis (2,2,6,6-tetramethyl-4-piperidinyl) ester

1,5-dioxaspiro (5,5) undecane-3,3-dicarboxylic acid (Cyasorb UV-500);

* an acid bis (1,2,2,6,6-pentamethyl-4-piperidinyl) ester

1,5-dioxaspiro (5,5) undecane 3,3-dicarboxylic acid (Cyasorb UV-516);

* N-2,2,6,6-tetramethyl-4-piperidinyl-N-amino-oxaimide;

* 4-acryloyloxy-1,2,2,6,6-pentamethyl-4-piperidine.

* 1,5,8, 2-tetrakis [2 ', 4'-bis (1' ', 2' ', 2' ', 6' ', 6''pentamethyl-4' '- piperidinyl (butyl) amino) -1 ', 3' / 5'-triazin'-6'-yl] -1,5,8,12-tetraazadodecane.

HALS PB-41 (Clariant-Huningue S.A.)

Nylostab S-EED (Clariant-Huningue S.A.)

3-dodecyl-1- (2,2,6,6-tetramethyl-4-piperidyl) pyrrolidine-2,5-dione

Uvasorb HA88

1,1 '- (1,2-ethanediyl) -bis- (3,3', 5,5'-tetramethyl & H-11h piperazinone) (Good-Riter 3034)

1,1 ', 1- (1,3,5-triazine-2,4,6-triyltris ((cyclohexylimino) -2,1-ethanediyl) -tris- (3,3,5,5-tetramethylpiperazinone) (Good -riter 3150)

1,1 ', 1- (1,3,5-triazine-2,4,6-triyltris ((cyclohexylimino) -2,1-ethanediyl) -tris- (3,3,4,5,5-tetramethylpiperazinone) (Good-Riter 3159).

In a preferred embodiment, the oligomer of N- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol and succinic acid (Tinuvin 622) is used for practical use; ((6-morpholine-S-triazine-2,4-diyl) (2,2,6,6-tetramethyl-4-piperidinyl) iminohexamethylene- (2,2,6,6-tetramethyl-4-) piperidinyl) amino (Cyasorb UV 3346);

polymethylpropyl-3-oxy- [4- (2,2,6,6-tetramethyl) piperidinyl] siloxane (Uvasil 299); 7-oxa-3,20-diazaspiro- [5.1.11.2] heneicosan-21-one, 2,2,4,4-tetramethyl-20- (oxiranylmethyl) u oligomer (Hostavin N30);

Propanedioic acid [(4-methoxyphenyl) methylene] -bis- (1,2,2,6,6-pentamethyl-4-piperidinyl) ester (Sanduvor PR 31); N, N '' - [1,2-ethanediylbis [[[4,6-bis [butyl (1,2,2,6,6-pentamethyl-4-piperidinyl) amino] -1,3,5-triazin-2]] -yl] imino] -3,1-propanediyl]] - bis [N ', N' '- dibutyl-N', N '' - bis (1,2,2,6,6-pentamethyl-4-piperidinyl) -1 3,5-triazine-2,4,6-triamine (Chimassorb 119); HALS PB-41 (Clariant-Huningue S.A.); Uvasorb HA88; 1,1 ', 1' - (1,3,5-triazine-2,4,6-triyltris ((cyclohexylimino) -2,1-ethanediyl) -tris- (3,3,5,5-tetramethylpiperazinone) (Good- riter 3150);

1,1 ', 1' - (1,3,5-triazine-2,4,6-triyltris ((cyclohexylimino) -2,1-ethanediyl) -tris- (3,3,4,5,5) tetramethylpiperazinone (Good-Riter 3159).

The HALS content of the composition may, in principle, vary

0

- 00 0 * 0 0 ' · » 0 0 · • 0 0 0 0 • _ · 0 - 0 0 ··· • 0 000 0000 0 0 0 0 0

within a wide range, for example between 0.05 and 3% by weight, preferably between 0.1 and 2% by weight, and even more preferably between 0.2 and 1% by weight. If HALS is used, without activated carbon, the upper limit of the usable amount is largely determined by the effect of HALS release, but it was surprisingly found that this effect is less significant in the presence of activated carbon. In a preferred embodiment, high molecular weight HALS is used in the polyetherester film, for example Tinuvin 622, Uvasil 299, Cyasorb UV 3346 and Chimassorb 944, which are oligomeric or polymeric HALS compounds having a molecular weight greater than 1500, preferably greater than 2000.

Therefore, in fact, the HALS content of the composition of the invention is primarily determined by the concentration required to achieve the desired shelf life. This content is usually between 0.1 and 1.0% by weight.

The composition may optionally contain other additives, such as fillers, heat-oxidizing stabilizers, other light-assisting aids, such as triazoles or thioesters, processing aids, dyes, and the like.

The composition can be obtained in a manner known to the person skilled in the art, who will pay particular attention to the good dispersion of activated carbon and HALS in the composition, preferably by a method of preparing a masterbatch, in which the active compound concentrate is preferably produced in a twin screw extruder. coal (e.g., 10 to 40 weight percent) in a polyether ester or similar interchangeable polymer that

It is then blended into the polyetherester copolymer as desired. A twin-screw screw extruder is also preferably used for this purpose. HALS is also preferably added in the form of a masterbatch.

Moreover, it is also possible to incorporate the constituents into the melt by any other means, paying particular attention to achieving good dispersion, inter alia by virtually complete distribution of the carbon agglomerates to the primary aggregates, inter alia by means of high shear forces or by the use of dispersants.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be explained on the basis of the following examples and comparative experiments. The examples relate to only one type of copolyetherester and a specific combination of carbon black and HALS. However, since the mechanism of degradation of the copolyetherester affects the ether groups of the copolyether, any other copolyetherester could be used as a model, and since the activity of activated carbon lies in its large specific optical surface area and HALS activity is largely due to the nature of the proposed group present. samples, any other type of activated carbon and other HALS will result in a comparable result.

Examples 1 to 15

Used materials:

Arnitel EM 400: copolyetherester with polybutylene terephthalate as the hard segment and tetramethylene oxide as the soft segment

13\

segment, Shore D = 40 hardness, from DSM, The Netherlands. ,

Activated carbon: Black Pearls 880, premix in polyethylene carrier material, from Cabot, average particle size 16 nanometers.

HALS: Chimasorb 944, an oligomer of cyanuric acid and N, N-di (2,2,6,6-tetramethyl-4-piperidyl) -hexamethylenediamine from Ciba-Geigy, Switzerland.

Experimental part:

The compositions shown in Tables 1 and 2 were obtained by mixing Arnitel EM 400, activated carbon, and HALS in a 30 millimeter Verner & Pfleider twin screw extruder at 245 ° C; at 250 rpm and 10 kilograms per hour. All raw materials were fed into the extruder throat. The granules were formulated into a film using a Battenfeld 45 mm single-spindle extruder equipped with a 250 mm Verbruggen foil extension. The temperature setting was 220 ° C and ‘the exit slot · was set to 0.3 millimeter. Different film thicknesses were achieved by varying the film removal rate.

Aging:

Aging was performed by exposure of film samples to an Atlas VOM Ci 65A (weather-o-meter) equipped with a xenon lamp under the following conditions:

Internal filters: borosilicate S external: borosilicate S

Intensity: 0.35 V / m / nm at 340 nanometers

Temperature: black standard: 67 ° C.

black plate: 73 ° C.

 surface: 45 ° C

Relative humidity: 50 ± 10 percent

Dry / wet cycle: 102/18 minutes

The samples were removed at regular intervals and subjected to mechanical tests.

Mechanical testing:

The ductility of the films (elongation at rupture) was determined according to ASTM G 26 on a Zwick 1445 tensile testing machine. Dimensions of the test specimen according to DIN 53504S3, prism section, length: 12 millimeters, width:

millimeters. '

Composition and results:

The lifetime of the samples was defined as the period over which the elongation at break was reduced to less than 100 percent.

··

TABLE 1

Films with a thickness of 100 i of nickrometers ί Experiment 1 3 4 c ^r 5 ’ KALS, wt% 0 and  0 0 1 0,5: carbon black, wt% 0 0 and 2 2 1: [life time [hours] 24 200 150 600 7000 2000 Foil - 175 micron thick r From Experiment 7 8 Whose* 10’- KALS, wt% 0.5 o · '1- 0.5 % carbon black, wt% 0 1. · 2 X j lifetime [hours] 168 150 > 7000 > 7000 25 m thick roll; .kromětru- Experiment 11 12 , Λ5 14 ’ 15 Dec KALS, wt% 0 0.5 1 0,5- 0 carbon black, ‘wt% ] _ 0 ^; 2 ' 0 'i ž i t nc s t '(hrs) 20 May 4 8 i 163 ± č u  10 )

of the invention.

ta · · '· ·· ·· • · the • · • · · : · · • • · • · · 5 taC ··· • ta · ·· · · · • · ·

It can be seen from the above table that the life of the very thin film is expected to be considerably shorter than the life of the film. The activity of the carbon black (activated carbon) and HALS considered in the case of their separate use also appears to be dependent on the film thickness. Particularly in a 25 micron film, the activity of the carbon black is low. The synergistic effect of the soot + HALS combination is surprisingly great.

With a film thickness of 100 microns, the lifetime was found to increase nearly ten-fold compared to the sum of the separate effects of HALS and carbon black.

Example 16

In another experiment, the aging properties of 50 micron Arnitel PM 380 *) with 1 percent HALS and 1 percent carbon black were observed under the same conditions as in the previous experiments. After 1000 hours, the ductility was still measured at 300 percent. This finding again demonstrates the stability of the composition of the invention.

*) Arnitel PM 380: Polyetherester copolymer with polypropylene coated with ethylene oxide as a soft segment. Shore D-38 hardness, from DSM, The Netherlands.

Examples 17 to 24

Several foils were subjected to aging tests

Arnitel EM 400 (100 microns) containing different combinations of UV stabilizers- Test conditions were different from the 9 test conditions of the previous. The intensity was 0.28 V / m / nm at 340 nanometers and the black plate temperature was 50 ° C. The lifetime used • 4 ·

17 ..-.

dropped to less than 100 percent.

TABLE 2

Experiment 17 18 19 Dec 20 May 21 22nd 23 24 HALS Tin 0, 5 0, 25 0, 5 0.0 0.5 UV Stab Tin 234 0, 5 0.25 0.5 0, 0 soot 0, 0 0/4 1.0 O 1-1 1_ lifetime [hours] 125 400 280 600 48 80 250 1500

Tin 144 = Tinuvin 144, M = 665

Tin 234 = Tinuvin 234, UV absorber,

2- (2-hydroxy-3,5-di (1,1-dimethylbenzyl / phenyl) 2H-benzotriazole)

Note:

In the carbon black-free composition, the presence of an antioxidant was necessary; in this case, it was 0.25 weight percent Irganox 1010, a phenolic antioxidant from Ciba.

This experiment again demonstrates a very potent effect of activated carbon and a HALS stabilizer. Another advantage of the combination of the invention represented by Experiment 24 is that no antioxidant need be added.

.. · · ' • ·· ' • · • · • · '· • • · δ - • ·· • • · · · · · · * • • · • '· • ·· • Λ · · ··· • · • ·

......

WáJteazaS

PATENT CLAIMS

Claims (11)

A polyetherester copolymer composition comprising 0.1 to 10 weight percent activated carbon and 0.05 to 3 weight percent sterically hindered amine light stabilizer (HALS). Polyetherester copolymer composition according to claim 1, characterized in that it contains from 0.5 to 5% by weight of activated carbon and from 0.1 to 2% by weight of HALS, preferably from 0.5 to 3 and 0.2, respectively. up to 1% by weight. Polyetherester copolymer composition according to claim 1 or 2, characterized in that the ratio between the hard and soft segments in the copolyetherester is such that the Shore D hardness is 25 to 80. Polyetherester copolymer composition according to any one of the preceding claims, characterized in that the carbon: oxygen ratio in the polyalkylene oxide glycol from which the polyetherester copolymer is derived is between 2 and 4.3. Polyetherester copolymer composition according to any one of the preceding claims, characterized in that the average primary particle size in the carbon dispersion in the composition is 15 to 40 nanometers. Polyetherester copolymer composition according to any one of the preceding claims, characterized in that the molecular weight of the HALS is higher than 1500, preferably higher than 2000. • · ♦ * ·. • · • • ·· ·· 9 · 4 4 44 4 4 • · • * · • 4 4 • • · 't · • 4 · • • · ? 99- ··· • «· 9 · · · • · The polyetherester copolymer composition of claim 6, wherein the HALS is selected from the group consisting of Tinuvin 622, Uvasil 299, Cyasorb UV 3346 and Chimassorb 944. A film characterized in that it is made of a composition according to any one of claims 1 to 7. 9. A film made of a polyetherester copolymer composition comprising 0.5 to 3 weight percent activated carbon and 0.1 to 2 weight percent HALS, having a Shore hardness of 25 to 80 and having a carbon to oxygen ratio. in the polyalkylene oxide glycol from which the polyether ester is derived is between 2 and 4.3, the average particle size in the carbon dispersion in the composition is 15 to 40 nanometers, and the molecular weight of the HALS is greater than 2000. Use of a film according to claim 8 or 9 in the construction industry. • ·. ** · Use of a film according to claim 8 or 9 in roof structures.